Diagenode

Formation of the CenH3-Deficient Holocentromere in Lepidoptera AvoidsActive Chromatin.


Senaratne, Aruni P and Muller, Héloïse and Fryer, Kelsey A and Kawamoto,Munetaka and Katsuma, Susumu and Drinnenberg, Ines A

Despite the essentiality for faithful chromosome segregation, centromere architectures are diverse among eukaryotes and embody two main configurations: mono- and holocentromeres, referring, respectively, to localized or unrestricted distribution of centromeric activity. Of the two, some holocentromeres offer the curious condition of having arisen independently in multiple insects, most of which have lost the otherwise essential centromere-specifying factor CenH3 (first described as CENP-A in humans). The loss of CenH3 raises intuitive questions about how holocentromeres are organized and regulated in CenH3-lacking insects. Here, we report the first chromatin-level description of CenH3-deficient holocentromeres by leveraging recently identified centromere components and genomics approaches to map and characterize the holocentromeres of the silk moth Bombyx mori, a representative lepidopteran insect lacking CenH3. This uncovered a robust correlation between the distribution of centromere sites and regions of low chromatin activity along B. mori chromosomes. Transcriptional perturbation experiments recapitulated the exclusion of B. mori centromeres from active chromatin. Based on reciprocal centromere occupancy patterns observed along differentially expressed orthologous genes of Lepidoptera, we further found that holocentromere formation in a manner that is recessive to chromatin dynamics is evolutionarily conserved. Our results help us discuss the plasticity of centromeres in the context of a role for the chromosome-wide chromatin landscape in conferring centromere identity rather than the presence of CenH3. Given the co-occurrence of CenH3 loss and holocentricity in insects, we further propose that the evolutionary establishment of holocentromeres in insects was facilitated through the loss of a CenH3-specified centromere.

Tags
Antibody
iDeal ChIP-seq Kit for Histones
Beads

Share this article

Published
October, 2020

Source

Products used in this publication

  • ChIP kit icon
    C01010051
    iDeal ChIP-seq kit for Histones
  • cut and tag antibody icon
    C15410003
    H3K4me3 polyclonal antibody
  • Antibody ChIP icon
    C15410060
    H3K9me2 polyclonal antibody
  • default alt
    C03010022-220
    DiaMag anti-mouse IgG coated magnetic beads

       Site map   |   Contact us   |   Conditions of sales   |   Conditions of purchase   |   Privacy policy